Grid-ikon slide-valve



UNITED sierras rafrnivr orFIcE.

WM. W. HUBBARD, OF BOSTON, MASSACHUSETTS.

GRID-IRON SLIDE-VALVE.

Specification of Letters Patent No. 7,037, dated January 22, 1850.

To czZZ wiz-0m t may concern Be it known that- I, HLLIAM lV. HUB- BARD,of Boston, in t-he county of Suffolk and State of Massachusetts, haveinvented certain new and useful Improvements in Valves of Steam-Engines,and that the fol- .1

lowing description, taken in connection with the accompanying drawings,hereinafter referred to, forms a full and exact specification of thesame, wherein I have set forth the nature and principles of my' saidimprovements by which my invention may be distinguished from others of alike class, together with such parts as I claim and desire to havesecured to me by Letters Patent.

The figures of the accompanying plates of drawings represent myimprovements.

Plate 1, Figure l is a side elevation of a cylinder of a horizontalsteam engine and its appurtenances or appendages, with the front of thesteam chest removed. Fig. 2, is a plan of the same. Fig. 3 is anenlarged detailed sectional view, taken in the plane of the line A, BFig. 1, and Figs. 4 and 5 are detached plans respectively, of the valveseat and under side of the sliding valve. Plate 2, Fig. 6, is aperspective"view of the sliding valve, valve seat, and exhaust chamber,so separated or spread apart, as to show the details of construction ofeach clearly.

By recent improvements, which have been made in steam engines, the steamis introduced and discharged through several rectangular openings,formed in the valve seat, and sliding valve, at proper intervals apart,the capacity of all of which should be sufficient to receive anddischarge the greatest amount of steam required to drive the engine, atits utmost power and speed. By these arrangements, the traverse of thesliding valve is materially diminished, as are also thereby the frictionand wear and tear of the valve seat. In these improved arrangements, theexpansion valves are moved with the sliding valve, being pressed againstsaid sliding valve, by springs or otherwise, which permit their movementto vary the cut 0E. There has also been combined with said expansionvalves, a regulator or governor, and as the motion or traverse of thevalves is short, as above specified, the least spreading of the balls ofthe governor will affect the cut off and thereby regulate the working ofthe engine to a nicety.

In connection With these improvements which have been recently devisedby others, I have invented and combined an improved arrangement of theexhaust openings, or comunications or passages, for conducting theexhaust steam to the exhaust chamber, which arrangement is peculiarlyadapted to the valves having the several openings for inducting andeducting the steam as specifled, and considerably enhances their utilityand eectiveness.

A, A, A, in the several drawings, is the cylinder and Z), b, representsthe exterior casing of the steam chest, into which the steam may beintroduced on the side or top as desired.

The valve seat, a plan of which is shown in Fig. 4c has four or morerectangular openings, 0, c, c, 0,-d, eZ, CZ, (Z, cut through at properintervals apart, at each end of the same, as shown in said Fig. 4 and inFig. 3, so as to communicate with the passages e-f to the cylinder' ateach end of said cylinder. The sliding valve, a plan of the underside ofwhich, is shown in Fig. 5 has four or more corresponding rectangularopenings, cut through it at each end, at` exactly the same distancesapart as those through the valve seat, as shown at ZL, ZZ, Zz, Zar-Z, Z,Z, Z, Figs. 3 and 5. The expansion valve is made in two parts Z0 and Z,each partl having rectangular openings m, m, wia-a, n, n, and when theseopenings are over or in opposition with those in the valve seat, andsliding valve above referred tothe steam passes into the cylinder at oneor the other as the case may be, but when they are not so in oppositionthe supply is cut off. In Fig. 8 the parts are represented as inposition to permit the'supply of steam through the passage f, but tointerrupt it through that denoted at e, and it will readily be seen thata very slighttraverse of the valves is sufficient for the perfectoperation of the engine.

In the underside of the sliding valve, between and around therectangular openings above referred to, are mortised out, but not'spaces 0, 0, o, &c., 70 p about the cylinder (shown in Fig. 3 and bydotted lines in Fig. 4) through the medium of the rectangular mortisesor slots g, g, g, g, cut in the valve seat, and opening into saidchamber, as shown by dotted lines in Fig. 4.

This arrangementI is clearly represented in the perspective View, Plate2 Fig. 6 in Which the exhaust mortises 0, 0, o, &c., p, p, p, &c., inthe sliding valve between and around the inducting and educting passages7L, L, h, &c., z, z', i, &c., through said valve are colored blue forthe safe of distinction, as are also the elongated slots or openings g,g, g, g, in the valve seat with which these mortises or freely, andthrough which, the exhaust steam passes into the exhaust chamber g g, oneither side of the passages or rectangular pipes, e e-e e which pipesconvey the steam to and from the cylinder.

The expansion valve, as before suggested is made in two parts 7c and Zwhich are pressed against the sliding valve, so as to move With it bymeans of the long springs r 1"-7 r Fig. l. Their adjacent sides bearagainst the edges of the two metallic right angular movable stops s s,Which are guided in their movements by the slots t t, and guiding rodsshown at u u, Figs. l and 3. The guiding rods are fastened to the faceof the valve seat, and project through an opening, out out of the centerof the sliding valve, as shown at o o Figs. 3 and 5. These stops aremoved to and from each other by means of the projections w fw, from theshort shaft m, Which fit into notches formed in the inner sides of eachof said stops, as shown in Fig. 1, said shaft being turned by thespreading of the balls of the governor a a With 79 &c., communicatecrank ci, as Will be readily understood by inspection of Fig. l.

By the separation of the balls of the governor it Will be seen that thetWo parts of the expansion valve Will be moved apart, and the aperturesthrough the sliding valve diminished, and when they fall together ortoward each other the stops s s Will be similarly moved, and the outerends of the parts of the expansion valve abutting against the ends ofthe steam chest, will move them together again, and increase the area ofthe openings in the sliding valves. By this arrangement of the valves itWill be observed that the slightest variation of the governor Willinstantly, and effectually regulate the cut olil of the engine, therebymaking the engine most sensitive in its self-adjustment.

Having thus described my improvements, I shall state my claims asfollows lWhat I claim as my invention, and desire .to have secured to meby Letters Patent is The peculiar arrangement of the exhaust mortises orspaces o, o, 0, &c., p, p, p, &c., in the sliding valve between andaround the inducting and educting passages 7L, L, &c., z', z', &c.,through said valve, in combination with the elongated side slots orpassages g,g, &c., through the valve seat, leading to the exhaustchamber q g, the Whole arrangement and operation being substantially asherein above set forth.

WM. W. HUBBA-RD.

Vitnesses:

EZRA LINCOLN, J r., BENJ. C. PIPER.

